Gaius was a personal name borne by several Christians associated with Paul and John. The New Testament mentions Gaius of Macedonia, Gaius of Derbe, Gaius who hosted Paul, Gaius whom Paul baptized, and Gaius addressed in the Third Epistle of John.
Gaius of Macedonia accompanied Paul and was seized during the riot at Ephesus. Gaius of Derbe traveled with Paul toward Asia. Another Gaius hosted Paul at Corinth and joined his greetings, while the Gaius of 3 John was beloved, walked in the truth, and faithfully served fellow believers.
The sources distinguish several men rather than requiring all references to describe one person. Gaius was also the Roman form of the name Caius.